Nanomaterials: structural peculiarities, biological effects and some aspects of application

Nanosized materials have potential of practical application in a number of research fields, in industrial production, and in everyday life. However, at nanoscale level, many substances acquire new properties and therefore may become biologically very active. This has raised questions about the potential toxic effects of such materials on living organisms due to either intentional or unintentional contact with them. Thus, biological toxicity of novel nanoparticles (NPs) is a key issue which has to be clarified before their full integration in everyday life. The critical analysis of the literature data in respect of the positive and negative effects of nanomaterials is given in this chapter. Moreover, the current approaches for the determination of the biological effects of these types of substances are presented. In this case, main attention is paid to characteristics of the approaches used by authors for the express estimation of the total toxicity with the application of bacteria, Daphnia, and plants with the express control of the level of natural bioluminescence and enhanced chemiluminescence, the energy of the seed germination, and the efficiency of the photosynthetic apparatus of growing plants according to the estimation of chlorophyll fluorescence by the special "Floratest" biosensor. In addition to that, simple and effective methods for the control of cytotoxicity and genotoxicity are described including application of the modern analytical approaches based on the principles of biosensorics. Using the above-mentioned methodical approaches, two aspects of biological effects of such nanomaterials as: (a) NPs ZnO, AgO, FeO, TiO2, and others and (b) their colloidal substances are considered. Namely, their (a) biocidal activity (NPs) and (b) improvement of the nutrition of plants on calcareous soils (colloidal structures) are analyzed. A special attention is paid to the chemical and physical characteristics of the nanomaterials used by different spectrometric approaches including atomic force microscopy and scanning electron microscopy methods.